1. Technical Field
This invention relates to apparatus for unitizing goods by wrapping stretch film around the goods and more particularly to a mobile film wrapper.
2. Background Information
Today it is a common practice to prepare bulk goods for transport by wrapping them with stretch film. This unitizing process is generally implemented with large stationary film wrapping equipment set up at a fixed location. The load, i.e. goods to be wrapped, must be transported to said location and then passed through, or under, or rotated within, the stationary film wrapping apparatus.
Such stationary film wrappers have reached a high level of sophistication, generally provide excellent results, and accordingly have been widely employed. However, in certain applications, this fixed equipment exhibits significant limitations. The stationary film wrappers generally require auxillary conveyers, turntables or other material handling equipment for moving the load during the wrapping process. Further the stationary film wrappers are generally large and bulky limiting the locations at which they can be erected. They tend to be complex pieces of equipment, making their initial acquisition costs high and the risk of equipment failure and the cost of maintenance and repair not inconsequential. Further, since all goods must be transported to the wrapping station, a bottleneck can develop resulting in long lines and associated lost time and tied-up transport vehicles.
Many of the stationary film wrapping structures employ a pre-stretch device to stretch film as it is being applied to the load. Some employ a heated roller for this purpose, along with a separate fluid tank, pump, hoses and other hydraulic equipment.
Portable stretch film wrappers have previously been developed. Those known to applicants are either hand held, mounted on operator manuevered psuch carts, or robotically controlled. These are cold wrap devices and can be awkward and laborious to use, slow in operation, and wasteful of film.
A need thus exists for film wrapping apparatus which overcomes the shortcomings of both existing stationary and portable film wrappers.